Brent,
Please contact Trek, they have a very nice product that measures and
logs ESD events. It measures voltage (on contact) but it has ports for
external sensors.
The product has been designed for Hewlett Packard a few years ago.
David Pommerenke
From: brent.dew...@us.datex-ohmeda.com
My hand is up.
David Pommerenke
From: Luke Turnbull [mailto:luke.turnb...@trw.com]
Sent: Tuesday, May 27, 2003 8:23 AM
To: emc-p...@ieee.org
Subject: ESD Problem
Would the gentleman who is on the 61000-4-2 committee please put his
hand up?
Thanks,
Luke Turnbull
This message is from
Pommerenke
University Missouri Rolla
-Original Message-
From: drcuthb...@micron.com [mailto:drcuthb...@micron.com]
Sent: Wed 5/14/2003 5:38 PM
To: Pommerenke, David; drcuthb...@micron.com;
emc-p...@majordomo.ieee.org
Cc:
Subject: RE: HV
Dear Dave,
You are working on a difficult issue.
Every HV relay will breakdown before the contacts touch. The reason is
as follows:
When the contacts come closer the surface field strength
Increases. The field strength will increase so much, such
that the field emission current reaches
Dear Group,
There has been a discussion in EMC-PSTC on EUT response to different ESD
test voltage levels. Let me explain whay I understand about this
problem:
An EUT may respond monotonic: More stress, never reduces the EUT
response.
or
An EUT may show a non-monotonic response: It fails at
, but the
pulse is only 100 ns wide. So the requirements for the linearity
of the mixer is very high.
David Pommerenke
From: Chris Maxwell [mailto:chris.maxw...@nettest.com]
Sent: Friday, May 09, 2003 7:28 AM
To: Pommerenke, David; John Woodgate; emc-p...@majordomo.ieee.org
Subject: RE: ESD gun
in !emc-pstc that Pommerenke, David davi...@umr.edu wrote (in
a5d66e6b6f478b48a3cef22aa4b9fca378e...@umr-mail1.umr.edu) about 'ESD
gun verification' on Wed, 7 May 2003:
Brain,
Spelling!
I like to repeat: For verification you do not need calibrated
equipment or full bandwidth. The verification
, May 06, 2003 12:02 AM
To: Pommerenke, David; emcpost
Subject: Re: current-sensing transducer photos
David:
Thank you for the Committee Draft Version of the new ESD Standard. The
committee is to be commended for producing such a thoroughly researched
document that aims at improving test
Brain,
I like to repeat: For verification you do not need calibrated
equipment or full bandwidth. The verification is just a method to
increase trust in the calibration. If you use some homemade current
target and a 500 MHz scope, you will get a pretty good picture of the
waveform and detect
Dear John,
It depends on what you want.
But at first we need to discuss one issue of definition of
verificaiton, calibration or all kinds of similar words.
I define a calibration as a traceble measurement and a verification
as a measurement that helps to establish confidence that some
Dear Chet,
Modeling the frequency response is not a totally trivial task. In
general, there are two different design strategies:
1) Gauss-roll off
This scopes have an approximately Gauss-roll off with frequency. As
a
Consequence the ratio of F_sample to F_bandwidth has to be at
Kris,
In my reading of the standard, and the next modificaiton will include
that clearly, you need to test discharges to the shell of the USB
connector, as there will not be a connector in there all the time.
There is another strong arguemnt: The user might plug a charged (e.g.
hand-held)
Dear Group,
My experience is that with WEB-based systems there will be significantly
less participation. Posting of large documents, as people will not
carefully think about file size, compression down-sampling etc will make
it worse for people on dial-up connections. Discussions will be based
Dear Alex McNeil,
The intend of the standard is that each discharge is an individual
event. This means:
Electromagnetic consequence
===
All charges need to be drained before the next discharge is applied. You
may use an Ionizer, a conductive brush, a ground wire etc. to
Dave,
If you can give me the dimensions we can numerically calculate or
analytically estimate the waveform.
David Pommerenke
-Original Message-
From: David Heald [mailto:dhe...@tellium.com]
Sent: Thursday, October 31, 2002 4:58 PM
To: 'emc-p...@majordomo.ieee.org'
Subject: Circuit
Dear Group,
In dry conditions, not only the charging processes are enhancec, but the
severity (less risetime, higher peak current) is enhanced in general. For both
reasons, it is not uncommen to see ESD problems move around the world with the
local seasons.
Still, I would always try to debug
Dear Group,
The physics of air discharge (= the reason for the variatins, the effect of
humidity, speed of approach) is quite well explained in
D. Pommerenke, 'ESD: Transient Fields, Arc Simulation and Rise Time Limit' ,
Journal of Electrostatics 1995 36 (1995), pp. 31 - 54
David Pommerenke
share that data with me if it is in contact
mode and if the number of discharges at each level is large enough to obtain an
acceptable confidence level.
Regards
David Pommerenke
[Pommerenke, David] -Original Message-
From: Scott Douglas [mailto:dougl...@naradnetworks.com
Dear Group,
For most EUTs there is no need to do lower level testing in contact mode ESD.
The time is better spend (meaning a better test results uncertainty is
achieved) if the number of discharges is increased at the highest test level
(hundreds is a good number). Although it is possible
What you should take into account is the failure criteria for 61000-4-6 as seen
by the EU: No degradation beyond manufactueres specification.
Depending on the EUT just a few additional bit-errors at any of the tested
frequencies may be a fail. It may not be sufficient to just look at loss of
Just one comment on the Pelligrini Target:
We compared different Pelligrini Targets that were all made to the
specifications.
- Up to 1 GHz they perform reasonably close
- Above 1 GHz large differences show up, although they are all made to the
drawings.
- All of them show resonances in
Dear Group,
There is a big misunderstanding about verification, calibration, daily
check etc.
I am member of IEC TC77B WG-9 (ESD). We discussed what we want the user to do
and the present opinion is as follows (A new draft of the ESD standard will
reflect this position):
(1) Formal
Gabi,
The topic of an air-discharge spark gap is a little bit more complicated.
1) The breakdown voltage in air for a homogeneous field is given by the
Paschen-equations, providing
that the breakdown is a gas discharge process, not an explosive surface
process (happens at
high
Richard,
There are two reasons for this:
Physical reason
===
1) When you are approaching with an ESD simulator there is a distance at
which a spark MAY occur. This distance can be calculated ONLY for a
homogenious field quite well, using Paschen's equation. In a homogeneous
field
Ken,
The added uncertainty is exactly as large as if you have a piece of cable
(assume too short to have relevant losses) inbetween.
David Pommerenke
-Original Message-
From: Ken Javor [mailto:ken.ja...@emccompliance.com]
Sent: Friday, November 16, 2001 12:05 PM
To: Pommerenke, David
On the amps:
For emissions there are the following electrical criteria:
- Noise figure expect about 4 dB for a broadband amp 30 MHz - 2 GHz.
The noise figure is often larger at the lower frequencies if the
amplifier goes up to many GHz.
- Input SWR. This is important. Most broadband amps
that Pommerenke, David davi...@ece.umr.edu wrote
(in 9da8d24b915bd1118911006094516eaf0ba31...@umr-mail02.cc.umr.edu)
about 'EMC test table construction plans', on Thu, 1 Nov 2001:
For emissions and immunity you should not use any wood in the table. It
will
significantly (+/-2 dB up to 1 GHz for emissions
Doug,
For emissions and immunity you should not use any wood in the table. It will
significantly (+/-2 dB up to 1 GHz for emissions , more above, +/-10 dB for
immunity up to 1 GHz) change the test result. My experience has shown that
Styrofoam is basicly the best material. There are a couple of
I like to compile a list of all commercially available ESD simualtors for
system level tests to 61000-4-2:
In my list I have:
KeyTek Minizap
KeyTek KeyTek 2000
Schaffner 435
Schaffner 432
EM-TestESD-30c
EM-TestESD unit to universal tester UCS 500
John,
Quite true.
But on the other side: If a softerror occurs in the field, it is very hard
to determine what caused it. Thus, we probably do not know how many
ESD-softerrors occur on consumer products in the field. But often there is
'No trouble found' on customer returns. This does not
Richard,
Presently, the IEC 61000-4-2 standard is being revised. The main aim of the
revision is:
Improve the repeatability of test results !
This includes a discussion on the number of discharges. But increasing them
is meeting lots or resistance:
People simply do not want to increase
Dear Richard,
Hewlett Packard tests to more than 15 kV.
But please be aware: The severeness of an ESD tests does not always increase
with the test voltage. Depending on the physical failure mechanism (energy,
current, derivative, fields, E-field, H-field, etc.) it will go down with
voltage for
I upgraded a chamber at hp and looked at:
1) How to pass the 16 point call up to 3 GHz
2) How to upgrade /change add absorbers
3) Which commercial antenna works best from 26 Mhz - 3 GHz
4) How much power is needed.
5) How well does the signal repeat.
6) Field probes
7) etc.
The lab is
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